Injector for injecting caustic or acid fluids



R. .J; CHAMBERS 2,576,282

INJECTOR FDR INJECTING CAUSTIC OR ACID FLUIDS Nov. 27, 1951 Filed June28. 194';

INVENTOR. RUSSELL J. CHAMBERS ATTORNEY I BY Patented Nov. 27, 1951INJECTOR FORINJECTI-NG GAUSTIG R ACID FLUIDS Russell J. Chambers, CedarRapids, Iowa Application June 28, 1947, Serial No. 757,885

3 Claims. 1

This invention relates to improvements in injectors particularly'ofthe-type adapted to inject highly caustic or acid fluids into water orsteam systems for the-purposes of'conditioning them.

Withunits of this type, the corrosive action of the caustic acidusuallydestroys the working parts in extremely short order even whenexpensivemater-ials are usedin their manufacture. In-

jectors of this type must also inject the caustic or acid fluid intoboiler feed and steam lines underconsiderablepressure.

It is anobject of'this" invention, therefore, to provide an injectorwhich is. automatic in its operation, which wil-l resistdestruction fromthecorrosive action of caustic or acid fluids, and-which will operate atpressures up to ashigh as five hundred pounds persquare inch.

It is also an object of this invention to provide an injectorby' whichthe amount of injection of the fluid may-be readily controlled;

Ittis a further object of this invention. to provide: an injector whichvhas a: minimum number of moving working partsand which maybeeconomically manufactured and operated.

Theseaobject's areiattained by providing a pump unit: consisting of twochambers connected by a tube: or'ductl The upper chamber has positionedthereini an electrical. immersion heater. The lower chamber contains arubber sack substantially completely filling the interior of. suchchamber. The interior of the sack is connected to the source of. supplyof caustic. or acid fluid and to thewater' or: steam ineinto which thefluid is to be injected. Acheckcvalve is positioned between suchinterior andrthe: reservoir and automatically closes when pressure isgreater than atmosphere. Another checlcvalve is positionedbetween suchinterior and the line into which injection: is to; be made. This checkValve is automatically closed: by pressure in such line and opens onlywhen the; pressure in. the interior of the sack and lowerchamber-exceeds such line pressure. The upper chamber: and: that. partof the lower chamber exterior of; thesaick; is: completely filled withalcohol or otherfiuiidwhich has a low boiling pointand: high expansion.when converted to vaport: The: actionof: the heater may be controlled byan' adjustable timing device. When the element is heated the alcohol.boils and: converts to vapor exerting a. high pressure in the upperchamber. When this. pressure exceeds the pressure in the water feed lineor steam line into which caustic: fl uidis. to be injected, it willcause thesack to be compressed and Will urge the fluid from. theinterior of the sack into such line. As

soon as the heater is disconnected the alcohol vapor condenses and thepressure in the upper acteristic of the invention, are set forth withparticulariiw in the appended claims... The invention. itself; however,both as to its organization and its method of operation, together withadditional objects and: advantages thereof, will best be understood fromthe following description of a. specific embodiment when read in;connection with. the accompanying drawing, in which:

Fig. 1 is a View in plan elevation of an injector embodying. theinvention;

Fig. 2gis a view in endelevationof such injector;

Fig. 3ais a sectional Viewv taken on the line 3-3 of 'Fig. 2; and

Fig. 4'. is a; fragmentary sectoinal view taken on the line i e-of Fig.3.,

Referring to the drawing by reference numerals, the: injector consistsof, two connected chambers. Thev chambers and connections between them:are all formed of standard high pressure steel pipe fittings, such asnipples, Ts, couplings, plugs, and, flanges. These fittings are made: ofsections strong. enough to withstand pressures of well over five.hundred pounds per square inch. The upper chamber in consists. of a.nipple H- to one end. of which is threaded a coupling i2 and to theother end a. T I3, An electrical immersion heater Id of standard designsupplied with terminals I5 is threaded into. the coupling l2: andprojects a substantial distance into the chamber 10. The lower chamberI6 is. also formed of a nipple H to one end of'which is connected aflange It and to the other end a T [9. The. two chambers are connectedby a nipple Elli between the two, Ts l3 and i9. The lower chamber itcontains a rubber sack 2|. This sack substantially completely fills thearea of such chamber. It is preferably made of pure latex rubber whichwill remain flexible and which will resist the action of the caustic oracid fluid which is tobe pumped by the injector. The end 22 of the sack2! is stretched over the surface of the flange 18- and a fibre washer 23is inserted between such end and the flange. Another flange 2 1 isbolted to the flange 13 by bolts and nuts 25' and grips the ends- 22between itself and the flange it. A reducer 26 fits within the flange24. Its inner face holds a U-shaped copper tube support 27 The support21 is almost coextensive-withthe sack 2! when in its extended 'cools andthe vapor pressure decreases.

condition for the next injection cycle. length of time of theenergization of the immershape. Its purpose is to hold the sack 2| insuch extended position even when it is collapsed and thus prevent itfrom being forced out through the reducer 26. A small T 28 is connectedby a nipple 29 to the reducer 26. A check valve 3|! of standard designis fitted to one opening of the T 2 3 and opens toward the T to permitfiuid to be drawn into the sack 2|. Another check valve 3| is Secured tothe opposite end of the T 28 and operates to permit fluid to pass out ofthe sack 2|. To install the device for operation, the check valve 30 isconnected by piping with a reservoir for the caustic or acid fluid andthe check valve 3| is connected indirectly by piping or directly to thewater or steam pipe line into which injection of the caustic or acidfluid is to be made. The check valves 3!) and Si are of standardconstruction with the exception that they should preferably be made ofacid-resisting steel. The upper and lower chambers IQ and I are mountedas a unit on a base 32 by a bracket member 33. A 'panel 34 is mounted onthe base 32 and extends across the face of the unit. In the panel 34there is mounted a pressure gauge 35, a timing device 36, and anadjuster 3'1, all of standard design. A cover member 38 may be placedover the injector unit.

In order to charge the unit for operation, it'is preferable'to connectit in the line, bleed all of the air from the connecting tubing andsack, and

to fill such tubing, check valves 30 and 3|, T28. nipple 29, andinterior of the sack 2| with the caustic or acid fluid which is to beinjected. The sack 2| will then be extended to substantially its fullamount as is shown in Fig. 3. When this has been done, the remainingarea of lower chamber It, the interior of connecting nipple 2|], and allof upper chamber ID are completely exhausted of air and filled withalcohol, using either or both end openings in the Ts I3 and Hi. Whenthis has been accomplished, plugs 39 and 43 are inserted in such endopenings to seal the unit. The filling should take place when theimmersion heater is deenergized and cool and 'while the unit issubjected to atmospheric pressures. When the device is so charged, ifthe rubber sack 2| to collapse, forcing the fluid in such sack outthrough the check valve 3| into such line. During this action the checkvalve remains closed preventing pressure from backing up into thereservoir. It has been found that if the immersion heater I4 is heatedfor two and one-half minutes a pressure of substantially five hundredpounds per square inch is developed. When the heater is deenergized itThis creates a pressure less than atmophere in the chamber IE and theatmospheric pressure on the reservoir forces a new charge of liquidthrough the check valve 38 into the interior of the sack 2| againfilling it and placing the injector in The One important fea ture ofthis invention is the positioning of the upper chamber l0 above thelower chamber l6. As a result, when the alcohol vaporizes, the alcoholin the lower chamber and nipple 2|] will remain liquid. Its liquidlevel, even when the sack 2| is entirely collapsed, will never be belowthe connecting nipple 20. Hence, heat from the immersion heater I4 isnever conveyed in any harmful amount to the lower chamber I6 and thesack 2|.

By installing several injector pumps operating in timed sequence, acontinuous injection can be arranged. In such instance the amount of thecaustic or acid fluid being injected can be properly adjusted andproportioned to the flow of the water or steam into which such fluid isbeing injected. This adjustment is accomplished by regulatin the lengthof time that the immersion heater is heated.

The construction of the electrical timing device indicated generally at36 is not important per se and will not be described. Any device, suchas a telechron clock, in which there are substituted for the hour andminute hands discs with contact segments, or any other well-known typeof timing mechanism, may be used to regulate the time during which theimmersion heater 4 is energized. A control for the timing mechanism isindicated at 31. cuit in which the immersion heater I4 is connected anddisconnected from the source of supply by a direct switch, or by aninterposed relay switch controlled by the timing device, may beutilized. In spite of the fact that the timing device is by itself notimportant, it is an essential element of the combination. Its timingprevents the pump from becoming over-pressurized and coordinates theoperation of multiple pump units to obtain a steady delivery. The timingdevice also acts as an additional safety feature as it causes pressureto drop before the safety pressure factor has been reached even if therewere a failure of some other part such as a check valve.

Although only one embodiment of the invention is shown and describedherein, it will be understood that this application is intended to coversuch changes or modifications as come within the spiritof the inventionor scope of the following claims.

Iclaim:

1. An injector having an upper chamber and a lower chamber formed ofhigh pressure steel pipe nipples connected at respective ends by Ts andconnecting nipple, there being plugs in said TS to provide access tosaid chambers, an immersion type heater in said upper chamber, an inlethaving an inwardly opening check valve and an outlet having an outwardlyopening check valve both connected to said lower chamber, a flexiblerubber sack in said lower chamber having an expanded volumesubstantially equal to the volume of said lower chamber, the open end ofsaid sack being held between connecting flanges positioned on the end ofthe nipple comprising said lower chamber and communicating with saidinlet and outlet, and a charge of alcohol normally in liquid state insaid upper chamber duct and portion of the lower chamber exterior ofsaid sack, said alcohol being vaporized by said heater to cause thecollapse of said sack.

2. An injector having a chamber with several portions, one of saidportions having a length greater than its width, a collapsible elongatedsack, in said one portion having its open end Any well-known ciracvaasasack and said heater, said alcohol being vaporized 'by said heater whenenergized to collapse the side walls of said sack.

3. An injector having a chamber with several portions, one of saidportions having a length greater than its width, 9, collapsibleelongated sack in said one portion having its open end secured at oneend of said chamber, a valved inlet and outlet for said chambercommunicating 'with the interior of said sack, a rigid support membermounted within said sack and preventing the closed end of said sack frombeing moved to the open end thereof as said sack is collapsed,

an immersion heater in another of said portions, and a charge of alcoholnormally in liquid state filling the space within said chamber notoccupied by said sack and said heater, said alcohol being vaporized bysaid heater when energized to collapse the side walls of said sack.

RUSSELL J CHAMBERS.

REFERENCES CITED The following references are of record in th file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,314,376 Swan Aug. 26, 19191,603,593 Goodhue et a1 Oct. 19, 1926 2,039,999 Holyfield May 5, 19362,241,620 Shoeld May 13, 1941

